During 1969-72 138 total hip replacements were performed according to the technique of Müller. The mean age of the patients at operation was 65.4 years. The results were analysed 9-12 years after the operation. Deep infection occurred in two cases necessitating removal of the prosthesis. Eighteen per cent (25/138) were reoperated on because of mechanical failure, the prosthesis was exchanged in 20 of them. Radiological signs of loosening of either component were found in a further 17 patients; only two had symptoms. The total loosening rate was thus 33 per cent (42/138). Twenty-six patients with 31 operated hips died during the observation period. In all of these the aim of the operation was achieved. The remaining cases were evaluated for the long-term results of total hip replacement. These were found to be satisfactory in all of but two cases with symptoms of mechanical failure. Loosening of the femoral stem was associated with varus position, while no relationship was found between loosening of the acetabular cup and the degree of inclination.